681964141 has 2 divisors, whose sum is σ = 681964142. Its totient is φ = 681964140.

The previous prime is 681964109. The next prime is 681964189. The reversal of 681964141 is 141469186.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 348755625 + 333208516 = 18675^2 + 18254^2 .

It is a cyclic number.

It is not a de Polignac number, because 681964141 - 2⁵ = 681964109 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 681964094 and 681964103.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681964541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340982070 + 340982071.

It is an arithmetic number, because the mean of its divisors is an integer number (340982071).

Almost surely, 2^681964141 is an apocalyptic number.

It is an amenable number.

681964141 is a deficient number, since it is larger than the sum of its proper divisors (1).

681964141 is an equidigital number, since it uses as much as digits as its factorization.

681964141 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41472, while the sum is 40.

The square root of 681964141 is about 26114.4431493379. The cubic root of 681964141 is about 880.2117865776.

The spelling of 681964141 in words is "six hundred eighty-one million, nine hundred sixty-four thousand, one hundred forty-one".